Steam-boiler.



D. S. JACOBUS.

STEAM BOILER.

APPLICATION FILED ocr. 9. 1916.

1,967,078. Patented. May 21,1918.

re a as rare.

DAVID S. JACOBUS, 0F JERSEY CITY, NEW JERSEY, ASSIGNOR TO THE BABCOGK AND WILCOX COMPANY, OF BAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEY.

STEAM-BOILER.

Specification of Letters Patent.

Patented May 21, 1918.

Original application filed April. 10, 1916, Serial No. 90,059.. Divided and this application filed October 9, 1916. Serial 110124518.

To all whom it may concern:

Be it known that 1. DAVID S. JAcoBUs, a citizen of the United States. residing at Jersey City, in the county of Hudson, State of New Jersey, have invented certain new and useful Improvements in Steam-Boilers, of which the following is a specification.

My invention relates to steam boilers more particularly to those of the general Stirling type and will be understood by reference to the accompanying drawing, showing a vertical longitudinal section of a boiler constructed and arranged as hereinafter described. The present application is a division of my application Serial No. 90,059, filed April 10, 1916. a

The boiler shown comprises three upper steam and water drums, 1, 2 and 3 connected by banks of tubes 4, 5 and 6 to a mud drum 7. I may use a single mud drum as shown, or a series of connected mud drums, and I intend to cover both constructions by the word lower chamber in the claims. The three upper drums must, however, be connected to this chamber whether it is in the form of one drum or several connected drums. The steam spaces of the front and middle steam and water drums are connected by circulators 8, and the steam spaces of the middle and rear steam and water drums are connected by circulators 9. spaces of the front and middle drums are connected by circulators 10, which support tiling 11, as shown.

The boiler illustrated is of the 4-pass type with a baffle 12 supported near the front of the front bank of tubes, extending upwardly from a point back of the bridge wall to near the upper end of the bank. The middle bank of tubes is provided with two baflles, one of which, 13 is supported upon the first row of tubes and extends downwardly from the middle steam and water drum, and the other, 14, is supported upon the rear row of tubes andextends upwardly from the mud drum. 1n the'third bank is a baffle 15 supported upon tubes at the rear of the bank and extending downwardly from the rear steam and water drum. A cross baflie or shelf 16 extends from the bafiie 14 to slibstantially the front row of tubesbf the rear bank. The gases thus flow upward in front of the front bank of tubes, across the latter at The water the upper part thereof into the secondary combustion chamber 17, downwardly over the tubes of the front bank, thence upwardly over the tubes of the middle bank, downwardly' over the tubes of the rear bank and upwardly in the final pass back of the rear bank to the outlet 18. By placing the baffle 12 as shown, the furnace gases pass over a comparatively small portion of the heating surface before they enter the chamber 17, which permits of an efiective secondary combustion in this chamber. In order to deflect the gases downward after they leave the middle bank, and to prevent direct impingement of the gases on the rear steam and water drum, 1 provide a baffle 19 which may be of special construction with curved tiles backed by cast iron members supported by rods 20. This baffle extends from the middle steam and water drum to substantially the first row of tubes of the rear bank. In some cases the baffle 19 may be made of cast iron without fire brick protection. The bailie 19 also prevents the hot gases striking the upper parts of the tubes of the rear bank. By so doing, there is practically no danger of overheating the tubes when the boiler is run at high ratings and the water level falls below the taps of the tubes.

A eed pipe 21 enters the rear drum 3 .and discharges into a trough from which the water is distributed to the drum; A plate 22 is placed in the rear drum between the steam inlets 9 and the dry pipe 23, to deflect any water in the steam toward the bottom of the drum.

1n the steam space of the rear drum is placed a dry pipe 23 with which the main steam outlet 24 is connected. If a superheater is to be used it is preferably located in the secondary combustion chamber 17 at the rear of the front bank of tubes. The form of superheater shown in the drawing comprises the cross boxes 25 and 26 to which the upwardly projecting U tubes 27 are connected. The boxes are supported in saddles resting upon the'cross beam 28 forming art of the structural work of the setting. he. box 25 is placed near the, rear of the front bank of tubes and at a higher level than the box 26. The box 25 is preferably laced far enough from the rear 0 the front ank of tubesto allow for the e cansion of the superheater tubes into the box and to allow a boiler tube to be passed between the rear of the first bank of tubes and the box 25 in replacing a boiler tube. The lower box 26 is in close proximity to the middle bank of tubes. The spacing apart of the superheater boxes, as shown, lessens the overturning moment and provides a superheater which does not require supports for the tubes other than the cross boxes or headers and their supporting sadsteam can be secured and supplied to a dles. The steam outlet 24 is connected to the box 25 so that the steam after flowing through the superheater tubes passes out through the connection 29.

{l-o prevent short circuiting of the gases I may provide a seal 30 between the lower end of-the baflle 12 and the bridge wall 31, and

a seal 32 between the mud drum and thefloor, as more particularly described in my application Serial No. 55,771, filed October 14, 1915. In the standard Stirling boiler, the front and rear steam and water drums are on substantially the same level and below the middle drum, and the main steam outlet isplaced on top of the middle drum. According to the present invention, the rear steam and water drum is set higher than the usual practice and is substantially at as high a level as the middle steam and water drum, and the main steam outlet 24 is placed on the top of the rear drum. Experiments have demonstrated that the water level in the rear drum of a standard Stirling boiler, with the steam space of the middle drum interconnected to both the front and rear drums by steam circulating tubes is higher under certain conditions of operation with a water containing a material amount of elements in solution than it is with a purer water. It is, therefore, not only advantageous, but highly important, to raise the rear drum to the level of the middle drum, when the feed water is of such nature that it will lead to high concentrations in the water contained in the boiler.

The present boiler is especially adapted to waters containing impurities which tend to produce foaming and priming and drier superheater than with the standard arrangement in which the steam is taken from the middle drum. By raising the rear drum above the standard position the dry pipe 23 .is correspondingly raised above the water level in the rear drum and this eliminates any trouble which might occur when there is high water in the boiler with the rear drum at a lower level through the water being carried along with the steam into the dry pipe. With the steam spaces interconnected, as shown, the water level in the rear drum will at all times be well below the .i level of the dry pipe. Even should there water tubes.

the standard construction in which the steam is taken from the middle drum. Furthermore, in the boiler shown, there is no danger of filling the superheater with material carried along with the steam from the boiler as is the case when the steam is led from the middle drum with a water producing priming, in which case, the'water which prlmes over, carries with it solids in solution, which, onthe evaporation of the water in the superheater, will be deposited in the superheater.

The boiler shown lends itself to high rates of driving, even though the water may contain enough impurities to cause trouble through foaming and priming at a comparatively low rate of driving, when the steam outlet is placed on the middle steam and water dru'm.

What I claim and desire to secure by Letters Patent of the'United States is 1. A steam'boiler of the class described, comprising at least three upper transverse drums connected by banks of tubes to a lower water chamber, the rear upper drum being set at a higher level than'the front upper drum, a main steam ofi'take' leading from said-rear drum, baflles for giving the gases serial up and down passes over the banks of tubes, with an up pass in the middle bank and a down pass in the rear bank, a special baffle extending rearwardly from themiddle upper drum and arranged to direct the gases leaving the upper part of the middle bank into the rear bank to protect the rear drum from excessive heating, andan ofitake for the gases in the rear of the rearbank of a main steam ofltake leading from said rear' drum, baflies for, giving the gases-serial up and down passes over the banks of tubes,

with an up pass in the middle bank and a down pass in the rear bank, a special baflie extending rearwardly from the middle up.-

per drum and arranged to direct the gases leaving the upper part of the middle bank into the rear bank to protectthe rear drum n from excessive heating, and an oiftake for the gases in the rear of the rearbank of 3. steam boiler of comprising at least three upper transverse the class described mamas drums connected by banks of tubes to a lower Water chamber, the rear upper drum being at substantially the same level as the middle upper drum, a feed Water inlet leading into the rear upper drum, a main steam ofi'take leading from said rear upper drum, baffles arranged to give the gases serial up and down passes over the Water tubes with adown pass at the rear of the middle bank, and a special bafiie extending rearwardly from the middle upper drum and arranged to protectthe rear upper drum from excessive heating.

4. A steam boiler of the class described comprising at least three upper transverse drums connected by banks of tubes to a lower water chamber, the rear upper drum being at a higher level than the front upper drum, a main steam ofltake leading from the rear upper drum, baflies arranged to give the gases serial up and down passes over the water tubes, an offtake for the gases in the rear of the rear bank of Water tubes, a special baffle extending rearwardly from the middle upper drum and arranged to protect the rear upper drum from excessive heating, and a depending tension support for supporting the special bafie substantially as described.

5. A steam boiler of the class described comprising at least three upper transverse drums connected by banks of tubes to a lower Water chamber the front and middle upper drums being connected by Water circulators While the middle and rear upper drums are not directly connected as to Water spaces, the rear upper drum beingsubstantially the same level as the middle upper drum, a main steam ofitake leading from the rear upper drum, baflies arranged to give the gases serial up and down passes over the Water tubes with a down pass in the rear of the middle bank, and a. special baflie extending rearWardly from the middle upper drum and arranged to protect the rear upper drum from excessive heating.

In testimony whereof, I have hereunto signed my name in the presence of two subscribing wltnesses.

DAVID S. JACOBUS.

Witnesses:

EUGENE P. TERRY, JOHN A. W. DIXON. 

